[🐛 Bug]: WebDriver hanging in case of DevTools opened and tests are executed in multiple thread

[fenben5754]

What happened?

Create at least 2 test in different classes
Set the collection behavior to CollectionPerClass, and the MaxParallelThreads to 2
Create a simple webdriver and get the devtools session
Try to Run the tests in the same time from Test Explorer

result: tests are hanging

expected result: page should opened on all created browser

hint: works fine if I set the MaxPrallelThreads to 3

How can we reproduce the issue?

using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using OpenQA.Selenium.DevTools;
using System.Threading;
using Xunit;

[assembly: CollectionBehavior(CollectionBehavior.CollectionPerClass, MaxParallelThreads = 2)]
namespace SeleniumDevtoolMultiThread
{
    public class TestClass1
    {
        [Fact]
        public void Test()
        {
            TestClassHelper.OpenDevToolsAndNavigate();
        }
    }

    public class TestClass2
    {
        [Fact]
        public void Test()
        {
            TestClassHelper.OpenDevToolsAndNavigate();
        }
    }

    public static class TestClassHelper
    {
        public static void OpenDevToolsAndNavigate()
        {
            IWebDriver webDriver = new ChromeDriver();
            IDevTools devTools = webDriver as IDevTools;
            devTools.GetDevToolsSession();
            webDriver.Navigate().GoToUrl("https://www.google.com");
            webDriver.Quit();
        }
    }
}

Relevant log output

there is no log, the test just hanging

Operating System

Windows 10

Selenium version

.NET 4.8.1

What are the browser(s) and version(s) where you see this issue?

Chrome 110.0.5481.177

What are the browser driver(s) and version(s) where you see this issue?

ChromeDriver 110.0.5481.7700

Are you using Selenium Grid?

not used

[github-actions]

@fenben5754, thank you for creating this issue. We will troubleshoot it as soon as we can.

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Thank you!

[fenben5754]

hi @titusfortner I see you commented under other devtools relater issues
Maybe can you check this one as well please?
Thanks

[diemol]

Where does it hang? Is it still happening on 4.10.0?

[fenben5754]

Yes is happening with the latest version as well
Is hanging after start the browser

[diemol]

Why are you using a static method? Wouldn't that reuse the variable between threads?

[fenben5754]

is just for the more simple example usage
If I increase the max allowed threads to 3, is works fine, but if I add a new 3. test is hanging again
Seems to me the issue is coming if the parallel running tests count is the same or higher than the max allowed threads

[diemol]

Right.

We do not have time right now to check this. Would you please help us debug the code to identify on which line it hangs?

[nvborisenko]

Good news here I can reproduce the issue. Not good news: my local build is failing to go deeper into investigation.